Brake



V. BENDIX Sept. 10, 1929.

BRAKE Filed Deo. 3, 192'? INVENTOR VINCENT BENDN .IJT

ATTORN EY Patented Sept. l0, 1929.

UNITED STATES PATENT oFFlcE.

VINCENT BEND-IX, OI' CHICAGO, ILLIIOIS, ASSIGNOR TO BENDIX BRAKE COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

BRAKE.

Application led December 3 1927. Serial No. 237,385.

This 'invention relates to brakes, and is illustrated as embodied in'an internal expanding brake for an automobile. An object of the invention is to provide a simple afini inexpensive brake which is very power- One feature of the invention relates to formin the brake friction means of at least three oes arranged generally end to end, with the end shoes overlapping and preferabl jointed to the opposite ends of the centralY shoe, without throwing the stiiening webs of the end shoes oi center. This may best be accomplished bydisplacing the strifening web of the central-shoe at one side 'of the central plane of the shoes, preferably by a distance substantially equal to the thickness of the web.

Another im rtant feature has to do with Acentering the ction means, when the brake is released, by means acting on the central shoe directly and acting on the end shoes through their joints with the central shoe.

This novel centering means may include aspring, which preferably also urges the shoe away from the drum toward its released position, and which is illustrated as attached to a wedge lever acting on the shoe.

The above and other objects and features of the invention, including various novel and desirable details of construction, will be a parentfrom the followin description of t e illustrative embodiment s own in the accompanying drawing, in which Figure 1 is a verticalA sect-ion through the brake, just inside the head of the brake drum, and showing the brake shoes in side elevation' Figure 2 is a partial section, radially through the central shoe on the line 2 2 of Figure 1, showin the engagement of the centering lever witi the shoe; Y

Figure 3 is a partial section, on the line 3 3 of Figure 1, through the applying and anchoring means; and

Figure 4 is a partial section, on the line 4 4 of Figure 1, through one of the joints connecting the shoes.

The illustrated brake comprises a rotatable P0 drum 10, at the open side of which is a stationary support such and within which is means of the brake, sh shoes 14, 16, and 18 a to end. Preferably each slhoe lweldlng avflat web 20 to an arcuate outer rim 22 carrying the brake as a backing plate 12, arranged the friction own as including three rran'ed generally end is formed by lining 24, thus giving the shoe a' T-shaped cross-section (see Figure 2).

According to one feature ofnthe invention, and as best appears in Figure 4, the stiening webs of the end shoes 14 and 18 are substantially in the central plane of the brake shoe assembly, while'the stiifening web of the cenv ends.

The overlapped ends of shoes 14 and 18 ma be connected to the opposite ends of shoe 16 v y iioatmg joints, shown as including pivots 26 and 28. The ab ove-described arrangement makes shoes 14 and' 18 interchangeable in the same brake, brakes.

The brake is applied, against the resistance of return springs 30, b of floating y means such as a pair cams 32 engaging pairs of rollers 34 mounted on opposite ends of pivot pins 36 extending crosswise through the ends of shoes 14 and 18. Cams 32 are extended to form radial operatin 38 to anarml portions connected by a pivot Xed on a brake applying shaft 40 which extends through relatively large openings 42 in the cam Shaft 40 is bearin 44 welded to secure to the backing studs 48. Studs 48 may,

for the attachment of The anchor plates 46 a o posite ends, o ivots 36.

journaled in twostampings or ixed anchor plates 46 plate 12 by posts or if desired, also serve the return springs 30. re notched out, at their to receive the projecting ends en the drum 10 is rotating clockwise in Figure 1 at the time the brake is applied, the torque of all three shoes is transmitted to the anchor 36 of shoe 18; clockwise, the anchora pin 36 of the shoe 14r plates 46 through the pivot pin if the drum is turning counterge' is through the pivot and also in'right and left The above-described anchorage and applying means is more full?I described, and is claimed in my prior app ication No. 159,806, filed January 8, 1927.

According to an important feature of the invention, the shoe 16 is centered directly, and shoes 14 and 18 are centered indirectly through joints 26 and 28, by means such as a spring 50, shown as fastened at one end on the backing plate and connected at its other end to a wedge lever 52 fulcrumed on a pivot 54 carried by the backing plate. Lever 52 is preferably formed with a cam slot 56 emracing a pin 58. Pin 58 may be provided with a roller 60, to minimize friction, if desired. It will be noted that spring 50 also urges shoe 16 away from the drum toward its released position.

While one illustrative embodiment has been described in detail, it is not my intention to limit the scope of the invention to vthat particular embodiment, or otherwise than by the terms of the appended claims.

Iclaim:

1. A brake comprising three shoes, the two end shoes having stiening webs in the central plane of the shoes, and the central shoe having a stiiening web offset from said central plane by a distance substantially equal to the thickness of said web and overlapping the ends of said end shoes.

2. A brake comprising three shoes, the two `r end shoes having stiiening webs in.,thecen tral plane of the shoes, and the central shoe having a stilening web o'set from said central p ane by a distance substantiall equal to thetickness of said web and over apping the ends of said end shoes, in combination with means connecting the overlap d ends of the end shoes to the opposite endg of the central shoel y 3. A brake comprising at least three shoes arran ed end to end with the end shoes connecte by oating joints to opposite ends of the central shoe and anchoring alternatively on one or the otherof the end shoes, in combination with a centering lever acting on the central shoe directly and acting through said joints on the end shoes.

4. A brake comprising at least three oating shoes arranged end to end with the end shoes connected by iioating joints to oppo- V site ends of the central shoe and anchoring alternatively on one or the other of the end shoes, in combination with a yieldingly-operated centering lever acting on the central shoe directly and acting through said joints on the en'd shoes. f

5. A brake comprising, in combination, a drum, at least three shoes arranged end to end and engageable with the drum, floating joints connecting the end shoes to opposite' ends of the central shoe, and a lever member acting on the central shoe and ur it tob ward a centered position with respect to the drum.

Y 6. A brake comprising, in combination, a drum, at least three shoes arranged end to' en'd and engageable with the drum, floating vjoints connecting the end shoes to opposite to center the central shoe when the brake is released.

In testimonyk whereof, I have hereunto signed my name. v

VINCENT BENDIX. 

